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1.
Sex Transm Dis ; 51(5): 367-373, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38346403

ABSTRACT

BACKGROUND: Sexually transmitted infections (STIs) have a high incidence in the US Armed Forces and can adversely impact service members' ability to perform their duties. Better knowledge of Mycoplasma genitalium (MG) epidemiology in the military is needed to understand the potential impact of this emerging pathogen on force readiness. METHODS: We conducted cross-sectional analyses of data from US Army service members and other Military Health System beneficiaries participating in a trial of an STI/HIV behavioral intervention at Fort Liberty, NC, and Joint Base Lewis-McChord, WA. At enrollment, participants completed questionnaires and provided biological specimens for nucleic acid amplification testing for MG, Chlamydia trachomatis (CT), and Neisseria gonorrhoeae (NG). We used principal component analysis and robust Poisson regression to examine associations between participant characteristics and prevalent urogenital MG. RESULTS: Among 432 participants enrolled between November 2020 and February 2023, 43 had MG (prevalence, 10.0%), of whom 13 had coinfection with another bacterial STI (all 13 were positive for CT, with 1 also positive for NG). The prevalence of MG was significantly higher among female (13.5%) versus male (7.6%; P = 0.048) participants and non-Hispanic Black (14.9%) versus non-Hispanic White participants (6.6%; P = 0.045). Single relationship status and increased number of recent sexual partners were correlated, and their component was associated with higher MG prevalence (adjusted prevalence ratio, 2.11; 95% confidence interval, 1.29-3.48). CONCLUSIONS: The high prevalence of urogenital MG among Military Health System beneficiaries highlights the importance of understanding the potential clinical sequelae of MG and conducting additional epidemiologic research in military settings.


Subject(s)
Chlamydia Infections , Gonorrhea , Mycoplasma Infections , Mycoplasma genitalium , Sexually Transmitted Diseases , Female , Humans , Male , Chlamydia Infections/epidemiology , Chlamydia Infections/complications , Chlamydia trachomatis , Cross-Sectional Studies , Gonorrhea/microbiology , Mycoplasma Infections/microbiology , Neisseria gonorrhoeae , Prevalence , Sexually Transmitted Diseases/microbiology , Clinical Trials as Topic
2.
PeerJ ; 10: e14197, 2022.
Article in English | MEDLINE | ID: mdl-36217387

ABSTRACT

Ericusa ngayawang sp. nov. is described from shells preserved in the Middle Miocene Cadell Formation in the western Murray Basin of South Australia. At the time the Murray Basin was part of the Southeastern Australian Marine Biogeographic Province. Ericusa ngayawang is a small heavily costate species of Ericusa with clear affinities to the Early Miocene E. atkinsoni of Victoria and Tasmania but can be distinguished from it by its smaller size, more slender proportions and its heavily costate body whorl. Ericusa atkinsoni and its relative, E. macroptera, inhabited the basins to the east of the Murray Basin during the Late Oligocene and Early Miocene but were extinct there before the end of the Burdigalian Stage of the Early Miocene. The persistence of E. ngayawang into the Langhian Stage of the Middle Miocene is another piece of evidence for partial biogeographic isolation of the western Murray Basin from the rest of the Southeastern Australian Province during the Miocene.


Subject(s)
Gastropoda , Animals , South Australia , Phylogeny , Fossils , Victoria
3.
PeerJ ; 8: e10466, 2020.
Article in English | MEDLINE | ID: mdl-33391869

ABSTRACT

The crocodylian fossil record from the Cenozoic of Australasia is notable for its rich taxonomic diversity, and is primarily represented by members of the clade Mekosuchinae. Reports of crocodylian fossils from Australia date back to the late nineteenth century. In 1886, Charles Walter de Vis proposed the name Pallimnarchus pollens for crocodylian fossils from southeast Queensland-the first binomen given to an extinct crocodylian taxon from Australia. Pallimnarchus has come to be regarded as a large, broad-snouted crocodylian from Australia's Plio-Pleistocene, and numerous specimens, few of which are sufficiently complete, have been assigned to it by several authors throughout the twentieth century. In the late 1990s, the genus was expanded to include a second species, Pallimnarchus gracilis. Unfortunately, the original syntype series described as Pallimnarchus pollens is very fragmentary and derives from more than one taxon, while a large part of the subsequently selected lectotype specimen is missing. Because descriptions and illustrations of the complete lectotype do not reveal any autapomorphic features, we propose that Pallimnarchus pollens should be regarded as a nomen dubium. Following this decision, the fossil material previously referred to Pallimnarchus is of uncertain taxonomic placement. A partial skull, formerly assigned to Pallimnarchus pollens and known as 'Geoff Vincent's specimen', possesses many features of diagnostic value and is therefore used as basis to erect a new genus and species-Paludirex vincenti gen. et sp. nov. A comprehensive description is given for the osteology of 'Geoff Vincent's specimen' as well as aspects of its palaeoneurology, the latter being a first for an extinct Australian crocodyliform. The newly named genus is characterized by a unique combination of premaxillary features such as a distinctive arching of the anterior alveolar processes of the premaxillae, a peculiar arrangement of the first two premaxillary alveoli and a large size disparity between the 3rd and 4th premaxillary alveoli. These features presently allow formal recognition of two species within the genus, Paludirex vincenti and Paludirex gracilis comb. nov., with the former having comparatively more robust rostral proportions than the latter. The Paludirex vincenti holotype comes from the Pliocene Chinchilla Sand of the Darling Downs, south-eastern Queensland, whereas the material assigned to Paludirex gracilis is from the Pleistocene of Terrace Site Local Fauna, Riversleigh, northwest Queensland. Phylogenetic analyses recover Paludirex vincenti as a mekosuchine, although further cladistic assessments are needed to better understand the relationships within the clade.

4.
Proc Biol Sci ; 285(1881)2018 06 27.
Article in English | MEDLINE | ID: mdl-30051855

ABSTRACT

Simultaneously analysing morphological, molecular and stratigraphic data suggests a potential resolution to a major remaining inconsistency in crocodylian evolution. The ancient, long-snouted thoracosaurs have always been placed near the Indian gharial Gavialis, but their antiquity (ca 72 Ma) is highly incongruous with genomic evidence for the young age of the Gavialis lineage (ca 40 Ma). We reconcile this contradiction with an updated morphological dataset and novel analysis, and demonstrate that thoracosaurs are an ancient iteration of long-snouted stem crocodylians unrelated to modern gharials. The extensive similarities between thoracosaurs and Gavialis are shown to be an almost 'perfect storm' of homoplasy, combining convergent adaptions to fish-eating, as well resemblances between genuinely primitive traits (thoracosaurs) and atavisms (Gavialis). Phylogenetic methods that ignore stratigraphy (parsimony and undated Bayesian methods) are unable to tease apart these similarities and invariably unite thoracosaurs and Gavialis. However, tip-dated Bayesian approaches additionally consider the large temporal gap separating ancient (thoracosaurs) and modern (Gavialis) iterations of similar long-snouted crocodyliforms. These analyses robustly favour a phylogeny which places thoracosaurs basal to crocodylians, far removed from modern gharials, which accordingly are a very young radiation. This phylogenetic uncoupling of ancient and modern gharial-like crocs is more consistent with molecular clock divergence estimates, and also the bulk of the crocodylian fossil record (e.g. all unequivocal gharial fossils are very young). Provided that the priors and models attribute appropriate relative weights to the morphological and stratigraphic signals-an issue that requires investigation-tip-dating approaches are potentially better able to detect homoplasy and improve inferences about phylogenetic relationships, character evolution and divergence dates.


Subject(s)
Alligators and Crocodiles/classification , Biological Evolution , Phylogeny , Alligators and Crocodiles/anatomy & histology , Animals , Bayes Theorem , Evolution, Molecular , Fossils/anatomy & histology
5.
PeerJ ; 5: e3458, 2017.
Article in English | MEDLINE | ID: mdl-28649471

ABSTRACT

New records of the Oligo-Miocene mekosuchine crocodylian, Baru, from Queensland and the Northern Territory are described. Baru wickeni and Baru darrowi are accepted as valid species in the genus and their diagnoses are revised. Both species are present in Queensland and the Northern Territory but are restricted in time, with B. wickeni known from the late Oligocene and B. darrowi from the middle Miocene. The broad geographic distributions and restricted time spans of these species indicate that this genus is useful for biochronology. The record of B. wickeni from the Pwerte Marnte Marnte Local Fauna in the Northern Territory establishes that the species inhabited the north-western margin of the Lake Eyre Basin (LEB) drainage system. More southerly Oligo-Miocene sites in the LEB contain only one crocodylian species, Australosuchus clarkae. The Pwerte Marnte Marnte occurrence of B. wickeni indicates that the separation of Baru and Australosuchus did not correspond with the boundaries of drainage basins and that palaeolatitude was a more likely segregating factor.

6.
Hisp Health Care Int ; 14(2): 73-80, 2016 06.
Article in English | MEDLINE | ID: mdl-27257220

ABSTRACT

INTRODUCTION: This study assessed health providers' perceptions of factors related to professional interpretation services and the association between these factors and the potential use of ad hoc interpreters. METHOD: Data were collected from a convenience sample of 150 health services providers at a large, regional health system in South Carolina. RESULTS: Providers rated "ability to communicate effectively during a clinical encounter" as paramount regarding the use of interpretation services. The most important factors related to the likely use of ad hoc interpreters (cutting corners) included locating a qualified interpreter, having to wait for a qualified interpreter, and technical difficulties regarding phone and video technology. CONCLUSION: Health care organizations may benefit from increasing staff awareness about patient safety and legal and regulatory risks involved with the use of ad hoc interpreters.


Subject(s)
Attitude of Health Personnel , Communication Barriers , Language , Physician-Patient Relations , Professional Competence , Translating , Awareness , Communication , Comprehension , Health Services Accessibility , Humans , Multilingualism , Patient Safety , Risk , South Carolina , Technology , Telephone
7.
PeerJ ; 3: e1408, 2015.
Article in English | MEDLINE | ID: mdl-26587359

ABSTRACT

New jaws and teeth referable to the rare thylacoleonid marsupial Wakaleo alcootaensis are figured and described. The species is the geologically youngest known member of the genus and is only known from the late Miocene Alcoota Local Fauna of the Northern Territory, Australia. A revised diagnosis of the species is presented which is found to be morphologically distinct from its congeners. W. alcootaensis can be distinguished from other species of Wakaleo by its greater size, deeply recessed masseteric fossa, more steeply angled I1, loss of P2, greater P3 to M1 ratio and loss of M3. Several characters of W. alcootaensis, including the increase in size, steeply angled I1, increase of the relative size of P3, and reduction of the molar row are present in at least some species of Thylacoleo. Phylogenetic analysis suggests that these character states are convergences and that there was parallel evolution in these two thylacoleonid lineages.

8.
Sci Rep ; 5: 13224, 2015 Aug 19.
Article in English | MEDLINE | ID: mdl-26288028

ABSTRACT

The early evolution of sauropod dinosaurs remains poorly understood, with a paucity of unequivocal sauropod taxa known from the first twenty million years of the Jurassic. Recently, the Early Jurassic of South Africa has yielded an assemblage of dental and post-cranial remains displaying a more apomorphic character suite than any other similarly aged sauropodomorph. These remains are interpreted as a new species of basal sauropod and recovered cladistically as the sister taxon to Vulcanodon +more derived Sauropoda, underscoring its importance for our understanding of this pivotal period of sauropod evolution. Key changes in the dentition, axial skeleton and forelimb of this new species suggest a genuine functional distinction occurring at the sauropodiform-sauropod boundary. With reference to these changes, we propose a scenario in which interdependent refinements of the locomotory and feeding apparatus occurred in tandem with, or were effected by, restrictions in the amount of vertical forage initially available to the earliest sauropods. The hypothesized instance of niche-partitioning between basal sauropodan taxa and higher-browsing non-sauropodan sauropodomorphs may partially explain the rarity of true sauropods in the basal rocks of the Jurassic, while having the added corollary of couching the origins of Sauropoda in terms of an ecologically delimited 'event'.


Subject(s)
Dinosaurs/anatomy & histology , Dinosaurs/classification , Fossils , Animals , Biological Evolution , Phylogeny , South Africa , Time Factors , Tooth/anatomy & histology
9.
PeerJ ; 3: e931, 2015.
Article in English | MEDLINE | ID: mdl-26019996

ABSTRACT

Thylacinus yorkellus is described as a new, moderately small-bodied species of thylacinid from the latest Miocene or, more likely, earliest Pliocene of South Australia. The new species can be diagnosed by the autapomorphic presence a strongly developed precingulid that terminates in a cuspidule on the anterobuccal face of the paraconid of the lower molars and a tiny basal anterior cuspidule on P 2, P 3 and the lower molars. It is found by cladistic analysis to be the sister species of the recently extinct Th. cynocephalus and distinct from the approximately coeval Th. megiriani from the Northern Territory. New dentary material is described and referred to Th. megiriani. These add character data and allow this species to be re-diagnosed based on autapomorphic character traits. Each of the three known late Miocene to early Pliocene Thylacinus species (Th. potens, Th. megiriani and Th. yorkellus) suggest that, instead of declining, there was a modest radiation of Thylacinus in the late Miocene.

10.
PeerJ ; 2: e547, 2014.
Article in English | MEDLINE | ID: mdl-25237601

ABSTRACT

New craniodental specimens that are referrable to the thylacinid marsupial, Thylacinus potens, are described from the late Miocene Alcoota Local Fauna of the Northern Territory, Australia. The remains include a largely complete maxilla and dentary, showing for the first time the anterior dentition of the dentary. The new remains indicate that Th. potens was a more variable species than previously recognised. The dentary, in particular, is more gracile, than other specimens referred to this species. A revised apomorphy-based diagnosis of Th. potens that takes this variability into account is presented. A cladistic analysis supports previous analyses that placed Th. potens in a derived position within Thylacinidae, close to the modern Th. cynocephalus. New estimations of body size are made using published regressions of dental measurements of dasyuromorphians as well as by assuming geometric similitude with Th. cynocephalus. All methods produce body mass estimates in excess of 35 kg.

11.
PLoS One ; 8(10): e75216, 2013.
Article in English | MEDLINE | ID: mdl-24130690

ABSTRACT

Eutherian mammals and saurischian dinosaurs both evolved lineages of huge terrestrial herbivores. Although significantly more saurischian dinosaurs were giants than eutherians, the long bones of both taxa scale similarly and suggest that locomotion was dynamically similar. However, articular cartilage is thin in eutherian mammals but thick in saurischian dinosaurs, differences that could have contributed to, or limited, how frequently gigantism evolved. Therefore, we tested the hypothesis that sub-articular bone, which supports the articular cartilage, changes shape in different ways between terrestrial mammals and dinosaurs with increasing size. Our sample consisted of giant mammal and reptile taxa (i.e., elephants, rhinos, sauropods) plus erect and non-erect outgroups with thin and thick articular cartilage. Our results show that eutherian mammal sub-articular shape becomes narrow with well-defined surface features as size increases. In contrast, this region in saurischian dinosaurs expands and remains gently convex with increasing size. Similar trends were observed in non-erect outgroup taxa (monotremes, alligators), showing that the trends we report are posture-independent. These differences support our hypothesis that sub-articular shape scales differently between eutherian mammals and saurischian dinosaurs. Our results show that articular cartilage thickness and sub-articular shape are correlated. In mammals, joints become ever more congruent and thinner with increasing size, whereas archosaur joints remained both congruent and thick, especially in sauropods. We suggest that gigantism occurs less frequently in mammals, in part, because joints composed of thin articular cartilage can only become so congruent before stress cannot be effectively alleviated. In contrast, frequent gigantism in saurischian dinosaurs may be explained, in part, by joints with thick articular cartilage that can deform across large areas with increasing load.


Subject(s)
Adaptation, Physiological/physiology , Bone and Bones/anatomy & histology , Bone and Bones/physiology , Animals , Dinosaurs , Mammals , Principal Component Analysis , Reptiles
12.
PeerJ ; 1: e170, 2013.
Article in English | MEDLINE | ID: mdl-24133635

ABSTRACT

The new species Chelodina (Chelodina) murrayi is described from the late Miocene Alcoota Local Fauna of central Australia, in the Northern Territory. The new species is based on shell fragments and can be diagnosed by a ventrally reflexed anterior margin of the plastron, a ventrally narrowed cervical scute and strongly dorsally curved margins of the carapace extending from approximately peripheral two to peripheral nine or ten as well as by a unique combination of characters. Within Chelodina the new species is part of the nominal subgenus and within that subgenus it is most closely related to the Chelodina (Chelodina) novaeguineae species group. This is not only the oldest record but also the most southerly occurrence of this species group.

13.
Am J Emerg Med ; 31(5): 852-4, 2013 May.
Article in English | MEDLINE | ID: mdl-23558062

ABSTRACT

BACKGROUND: Myoclonus is a well-recognized side effect of etomidate when given in induction doses for rapid sequence intubation. Most of the data reported on myoclonus with emergency department (ED) sedation doses are reported as a secondary finding. STUDY OBJECTIVES: Our objective was to prospectively quantify the incidence and duration of myoclonus associated with the administration of etomidate in the lower doses given for procedural sedation in the ED. METHODS: This was a prospective descriptive study performed between September 2008 and September 2010 at an urban teaching hospital ED with approximately 50000 patient visits per year. Procedural sedation was performed at the discretion of the treating emergency physician, and adult patients receiving etomidate were eligible for enrollment. The occurrence and duration of myoclonus were observed and recorded. Any interference of myoclonus with the ability to complete the procedure was recorded, and adverse effects were identified. RESULTS: Thirty-four eligible subjects were enrolled, and 36 separate sedation procedures were performed. The mean initial etomidate dose was 0.13 mg/kg (range, 0.077-0.20), and the mean total etomidate dose was 0.15 mg/kg (range, 0.077-0.29). Myoclonus was noted in 26 (72%) of 36 sedations. Mean time to onset of myoclonus was 50 seconds (range, 15-146), and the mean duration was 93 seconds (range, 03-557). Myoclonus interfered with the procedure in only 1 (3%) of 36 attempted procedures, and no procedure was unsuccessful because of myoclonus. CONCLUSION: Myoclonus associated with sedation doses of etomidate was common but rarely interfered with the completion of a procedure.


Subject(s)
Etomidate/adverse effects , Hypnotics and Sedatives/adverse effects , Myoclonus/chemically induced , Adolescent , Adult , Aged , Aged, 80 and over , Dose-Response Relationship, Drug , Emergency Service, Hospital , Female , Humans , Incidence , Male , Middle Aged , Myoclonus/epidemiology , Prospective Studies , Time Factors , Young Adult
14.
Proc Natl Acad Sci U S A ; 109(7): 2428-33, 2012 Feb 14.
Article in English | MEDLINE | ID: mdl-22308330

ABSTRACT

The extensive Early Jurassic continental strata of southern Africa have yielded an exceptional record of dinosaurs that includes scores of partial to complete skeletons of the sauropodomorph Massospondylus, ranging from embryos to large adults. In 1976 an incomplete egg clutch including in ovo embryos of this dinosaur, the oldest known example in the fossil record, was collected from a road-cut talus, but its exact provenance was uncertain. An excavation program at the site started in 2006 has yielded multiple in situ egg clutches, documenting the oldest known dinosaurian nesting site, predating other similar sites by more than 100 million years. The presence of numerous clutches of eggs, some of which contain embryonic remains, in at least four distinct horizons within a small area, provides the earliest known evidence of complex reproductive behavior including site fidelity and colonial nesting in a terrestrial vertebrate. Thus, fossil and sedimentological evidence from this nesting site provides empirical data on reproductive strategies in early dinosaurs. A temporally calibrated optimization of dinosaurian reproductive biology not only demonstrates the primary significance of the Massospondylus nesting site, but also provides additional insights into the initial stages of the evolutionary history of dinosaurs, including evidence that deposition of eggs in a tightly organized single layer in a nest evolved independently from brooding.


Subject(s)
Behavior, Animal , Dinosaurs/physiology , Animals , Fossils , Reproduction
15.
PLoS One ; 7(2): e30228, 2012.
Article in English | MEDLINE | ID: mdl-22319562

ABSTRACT

BACKGROUND: Several clades of bivalve molluscs have invaded freshwaters at various times throughout Phanerozoic history. The most successful freshwater clade in the modern world is the Unionoida. Unionoids arose in the Triassic Period, sometime after the major extinction event at the End-Permian boundary and are now widely distributed across all continents except Antarctica. Until now, no freshwater bivalves of any kind were known to exist in the Early Triassic. PRINCIPAL FINDINGS: Here we report on a faunule of two small freshwater bivalve species preserved in vertebrate coprolites from the Olenekian (Lower Triassic) of the Burgersdorp Formation of the Karoo Basin, South Africa. Positive identification of these bivalves is not possible due to the limited material. Nevertheless they do show similarities with Unionoida although they fall below the size range of extant unionoids. Phylogenetic analysis is not possible with such limited material and consequently the assignment remains somewhat speculative. CONCLUSIONS: Bivalve molluscs re-invaded freshwaters soon after the End-Permian extinction event, during the earliest part of the recovery phase during the Olenekian Stage of the Early Triassic. If the specimens do represent unionoids then these Early Triassic examples may be an example of the Lilliput effect. Since the oldest incontrovertible freshwater unionoids are also from sub-Saharan Africa, it is possible that this subcontinent hosted the initial freshwater radiation of the Unionoida. This find also demonstrates the importance of coprolites as microenvironments of exceptional preservation that contain fossils of organisms that would otherwise have left no trace.


Subject(s)
Bivalvia , Feces , Fossils , Animals , Fresh Water , South Africa
16.
Nurse Pract ; 36(5): 48-52, 2011 May.
Article in English | MEDLINE | ID: mdl-21499068

ABSTRACT

Heat stroke is a life-threatening illness that requires prompt diagnosis and treatment. Early vital sign assessment and history gathering are key to identifying this disorder.


Subject(s)
Emergency Medical Services/methods , Heat Stroke , Nurse Practitioners , Acute Disease , Aged , Female , Heat Stroke/diagnosis , Heat Stroke/prevention & control , Heat Stroke/therapy , Humans
17.
Am J Forensic Med Pathol ; 32(1): 47-9, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20683321

ABSTRACT

Blunt force trauma to the chest can often result in diaphragmatic tears. These tears can go months without being discovered, until a secondary injury or circumstance causes an organ to herniate through the diaphragm. Special care should be taken at autopsy to determine the mechanism of injury of any tears in the diaphragm as this may influence the cause and manner of death. We present a case of a 28-year-old man who suffered multiple injuries in a motor vehicle collision. Six months later he presented with a left diaphragmatic tear and gastric fundal herniation, and died eventually.


Subject(s)
Death, Sudden/etiology , Diaphragm/injuries , Hernia, Diaphragmatic, Traumatic/complications , Accidents, Traffic , Adult , Diaphragm/pathology , Forensic Pathology , Hernia, Diaphragmatic, Traumatic/pathology , Humans , Ischemia/complications , Ischemia/pathology , Male , Stomach/blood supply , Stomach/injuries , Stomach/pathology , Time Factors , Wounds, Nonpenetrating/complications
18.
Proc Biol Sci ; 277(1682): 787-94, 2010 Mar 07.
Article in English | MEDLINE | ID: mdl-19906674

ABSTRACT

Aardonyx celestae gen. et sp. nov. is described from the upper Elliot Formation (Early Jurassic) of South Africa. It can be diagnosed by autapomorphies of the skull, particularly the jaws, cervical column, forearm and pes. It is found to be the sister group of a clade of obligatory quadrupedal sauropodomorphs (Melanorosaurus + Sauropoda) and thus lies at the heart of the basal sauropodomorph-sauropod transition. The narrow jaws of A. celestae retain a pointed symphysis but appear to have lacked fleshy cheeks. Broad, U-shaped jaws were previously thought to have evolved prior to the loss of gape-restricting cheeks. However, the narrow jaws of A. celestae retain a pointed symphysis but appear to have lacked fleshy cheeks, demonstrating unappreciated homoplasy in the evolution of the sauropod bulk-browsing apparatus. The limbs of A. celestae indicate that it retained a habitual bipedal gait although incipient characters associated with the pronation of the manus and the adoption of a quadrupedal gait are evident through geometric morphometric analysis (using thin-plate splines) of the ulna and femur. Cursorial ability appears to have been reduced and the weight bearing axis of the pes shifted to a medial, entaxonic position, falsifying the hypothesis that entaxony evolved in sauropods only after an obligate quadrupedal gait had been adopted.


Subject(s)
Biological Evolution , Dinosaurs/classification , Feeding Behavior , Gait/genetics , Animals , Behavior, Animal , Dinosaurs/anatomy & histology , Fossils , Gait/physiology , Paleontology , South Africa
19.
Proc Biol Sci ; 270(1525): 1753-8, 2003 Aug 22.
Article in English | MEDLINE | ID: mdl-12965005

ABSTRACT

A partial dinosaur skeleton from the Upper Triassic (Norian) sediments of South Africa is described and named Antetonitrus ingenipes. It provides the first informative look at a basal sauropod that was beginning to show adaptations towards graviportal quadrupedalism such as an elongated forelimb, a modified femoral architecture, a shortened metatarsus and a changed distribution of weight across the foot. These adaptations allowed the clade to produce the largest-ever terrestrial animals. However, A. ingenipes lacked specializations of the hand found in more derived sauropods that indicate it retained the ability to grasp. Antetonitrus is older than the recently described Isanosaurus from Thailand and is the oldest known definitive sauropod.


Subject(s)
Dinosaurs/anatomy & histology , Fossils , Phylogeny , Animals , Dinosaurs/physiology , Locomotion , Paleontology , South Africa
20.
Proc Biol Sci ; 269(1494): 915-21, 2002 May 07.
Article in English | MEDLINE | ID: mdl-12028774

ABSTRACT

One of the ultimate aims of systematics is the reconstruction of the tree of life. This is a huge undertaking that is inhibited by the existence of a computational limit to the inclusiveness of phylogenetic analyses. Supertree methods have been developed to overcome, or at least to go around this problem by combining smaller, partially overlapping cladograms. Here, we present a very inclusive generic-level supertree of Dinosauria (covering a total of 277 genera), which is remarkably well resolved and provides some clarity in many contentious areas of dinosaur systematics.


Subject(s)
Biological Evolution , Dinosaurs/classification , Animals , Phylogeny
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